Whole body vibration analysis for children in midi school bus

Abstract

The current study objective is to measure the whole-body vibration (WBV) transmitted to children of different age during the operation of midi bus. The results are compared with ISO 2631-1 (1997) health guidance criteria. The vibration values were measured at seat and children interface on x-longitudinal, y-transverse and z-vertical axes at different road profiles like highway road and rough road. The age of the children varies from 4 to 10 years. The finding of the study was at lesser the age more the vibration exposure because of children of less age have less tissue mass to dampen the vibration accelerations. The average root mean squared weighted acceleration, exposure time and estimated VDV on highway road were among the 1.05 to 3.07 m/sec2, 14 to 200 min and 12 to 24 m/sec1.75 respectively. And on rough road 1.16 to 5.65 m/sec2, 1 to 94 min and 15 to 46 m/sec1.75 respectively. This shows the health of the less age children are at risk, the OEM has to work on good suspension and engine mounts to isolate road and engine induced vibrations.